Heat interchanger



1936. A. L. STEVENS HEAT INTERCHANGER Filed Aug. 17, 1933 Patented Aug. 18, 1936 UNITED STATES HEAT INTEBCHANGER Arthur L. Stevens, Evanston, IlL, assignor to Katherine Stevens, Evanston, Ill.

Application August 17, 1933, Serial No. 685,503

4 Claims. (01. 257-139) The present invention relates to heat inter-'- changers and particularly to radiators.

One object of the invention is to provide a radiator of efllcient design and pleasing appearance.

Another object of the invention is to provide a radiator of non-rigid sheet metal construction.

Another object is to provide a radiator eflcient in design and economical to manufacture.

A further object is to provide a radiator havin a large heating surface and occupying a relatively small space.

Another object of this invention is to provide suitable fastening means to prevent distortion in the chamber due to excessive pressures.

Another object of this invention is to provide a radiator of light sheet metal construction, yet capable of withstanding excessive pressures.

A further object is to provide a simple and eilicient means for securing ornamental grilles to the steam chamber.

The foregoing and. other objects of the invention will be more fully described in the detailed specification which is to follow, taken in conjunction with the accompanying drawing.

' In present practice, heat interchangers are usually of cast metal construction, and are necessarily therefore, bulky and cumbersome and are expensive to manufacture. Usually, this form of radiator is cast in a plurality of pieces, said pieces being reassembled to provide sufllcient steam capacity and radiating surface, and are secured together by means of bolts, nuts, etc. This method of construction also increases the expense of the radiator due to the labor involved in assembling.

Various attempts have been made in the past to provide a sheet metal radiator, but most of these have not been successful-for two reasons.

The first is that the sheet metal plates have been so distinct that their construction required a number of die operations, and were therefore expensive, and the second reason is that they have not been properly guarded against distortion due to excessive internal pressures.

The present invention provides a radiator composed of sheet metal plates, these plates being formed in a. manner to permit economical manu- 0 facture and yet be capable of withstanding high 55 Fig, 1 is a fragmentary sectional view of one form of a steam chamber taken on the line i-i in Figs. 2 and 3.

Fig. 2 is a fragmentary sectional detailed view taken on the line 2-2 of Fig. 1.

Fig. 3 is a fragmentary sectional detailed view 5 taken on the line H in Fig. 1.

Fig. 4 is a fragmentary detailed sectional view of another form of steam chamber.

' F18. 5 is a fragmentary detailed sectional view of another modification of the steam chamber. 10

Fig. 6 is a fragmentary detailed sectional view of another form of steam chamber.

In the drawing, like reference characters apply to similar parts throughout.

As has been hereinbefore stated, the one dlflll5 culty encountered in the production of sheet metal radiators of this type has been, that it has been difilcult to provide a radiator which is at once of light metal construction, yet capable of withstanding high internal pressures, and which may be easily and cheaply formed. A construction accomplishing these objects is shown in Figs. 1, 2 and 3. As will be seen in these figures. a steam chamber 42 is formed by the two plates 43 and 44, these plates being spaced apart by rods at their edges. These rods 45 are preferably welded to the plates 43 and 44 to provide a suitable seal for the steam chamber 42. It should be noted that the steam chamber as illustrated in these figures comprises a plurality of relatively flat portions 46, and that these relatively flat portions are interconnected by curved portions 41. The curvature of the metal in these curved portions 41 has been found to provide sufficient rigidity to prevent distortion from excessive internal 35 pressures, but in order that the plates 43 and 44 may be of as light construction as possible, it has been found desirable to reinforce the relatively flat portions 46. In this instance, this is done by means of depressions 48 and 49, these depres- 40 sions being of a depth equal to approximately one-half of the thickness of the steam chamber in order that these depressed portions of the plates 43 and 44 may bear against each other and be welded together at the points ill. It will be 45 seen that when these points III are securely welded, it will provide a suitable reinforcement to prevent bulging or distortion of the relatively flat portions 46 of the steam chamber 42. While the inventor realizes that it is not new to weld the 50 opposite plates of a steam chamber at certain parts of their surface, yet, it is believed that the peculiar formation of the depressions as here shown is new and patentable, as it provides a very distinct advantage over the prior art. As will be clearly seen, the depressions l8 and II are formed in a rectangular shape, two walls of which form rather an abrupt angle to the plane of the flat surfaces 48, the other two walls being only slightly angularly displaced from this plane. The depressions I and 40 therefore reinforce the relatively flat portions l6 across their entire witlth. More important than this fact is the fact that the very slight angularity of the wall of the depression opposite the interconnecting curved portions 41 enables the manufacturer to form these depressions at the same time that the corrugations in the plates are formed, and with the same die. This is a very important feature in the manufacture of devices of this character, and since a depression with an abrupt angle on all of its side walls necessitates a separate operation for the forming thereof, it should therefore be seen that the applicant's structure providesa decided improvement over the prior art.

The construction here shown has the added advantage that the curved portions I! are capable of being bent a certain amount without damaging the steam chamber, either by way of appearance or efllciency. This enables the applicant to first form the steam chamber as shown in Figs. 1, 2 and 3, and to later bend this chamber into an arcuate shape or circular shape. In Figs. 4 and 5 there is illustrated a second method of reinforcing the steam chamber. In this instance, the plates 55 and 56 are also formed into flat portions 51 interconnected by curved portions Bl, the flat portions 51 having corrugations 59 formed therein to give the necessary rigidity to these flat portions. By examination of Fig 4, it will be seen that these plates are also formed so that at any point in the cross section of the steam chamber, the plates are divergent from their interconnecting curved portions 58 and therefore corrugations 59 maybe formed in one operation at the time the plate is bent into the flat portions I1 and the curved portions 58 in the same manner as is done in the previously described modification.

In Fig. 5, there is illustrated a third form of reinforcement in which the plates Oil and II are curved throughout their entire length to provide the necessary rigidity. It should be noted however, that these plates are made up of slightly curved portions 62, interconnected byabruptly curved portions 03. It has been found that the curvature of portions 62 is sumcient to give considerable rigidity, and at the same time the surfaces of these portions are at all points angularly divergent from their interconnecting curved portions ll, permitting their formation by a single die as hereinbefore described.

While I have shown and described several embodiments of my invention. I am aware that it may be variously modified without departing from the spirit and scope thereof as set forth in the appended claims.

I claim:

1. A heat interchanger wall including a pair of relatively flat portions interconnected by a curved portion, and depressions or corrugations so formed in the relatively flat portions that at any point in their cross section the opposed faces of the relatively flat portions are angularly divergent from their interconnecting curved portion.

2. A heat interchanger wall including a pair of slightly curved portions interconnected by an abruptly curved portion, and being so formed that at any point in their cross-section the opposed surfaces of the slightly curved portions are angularly divergent from their interconnecting abruptly curved portion. V

3. A heat interchanger wall including a pair of relatively flat portions angularly divergent from an interconnecting curved portion, and de ressions so formed in the relatively flat portions that the angle formed between the wall of the depression opposite the interconnecting curved portion and the plane of the flat portion is not greater than one-half of the angular divergence between the two flat portions.

4. A heat interchanger including a pair of plates; each of these plates comprising a plurality of flat portions interconnected by curved portions, and depressions so formed in the relatively flat portions that at any point in their cross-section the opposed faces of the relatively flat portions are angularly divergent from their interconnecting curved portion, means for sealing theedges of said plates to form a steam chamber, and means for securing the depressions formed in one of the plates to the corresponding depressions in the other.

AR'I'HUR L. STEVENS. 

